Even though I generally agree with your comment, I don't know where you got that replacement part from. AFAIK Librem 5 is not supposed to be modular and I certainly wouldn't pledge my money for such project unless it set its fundraising goal many times higher than they actually did. In devices like that, there's not much you can do to achieve hardware modularity without fighting with lots of constraints everywhere. The best I expect to see in similar devices is what Dragonbox Pyra does (and what Neo900 planned to do) - a sandwich with two PCBs, with one having the CPU and expected to be upgraded, and other one containing stuff that doesn't need to be upgraded as often, like various sensors, baseband etc. It wouldn't work for Librem 5 though, as it seems to be already very space constrained.
Librem 5's design makes it relatively easy to safely disable and not use the part you think is vulnerable, but you can't really replace them - that would put this project into a completely different budget category.
Librem 5's design makes it relatively easy to safely disable and not use the part you think is vulnerable, but you can't really replace them - that would put this project into a completely different budget category.